The Pellian Equation x² −5y² = 1 A General Method

n	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20
Pn	0	2	2	2	2	2	2	2	2	2	2	2	2	2	2	2	2	2	2	2
Qn	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1
an	2	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4
pn	2	9	38	161	682	2889	12238	51841	219602	930249	3940598	16692641	70711162	299537289	1268860318	5374978561	22768774562	96450076809	408569081798	1730726404001
qn	1	4	17	72	305	1292	5473	23184	98209	416020	1762289	7465176	31622993	133957148	567451585	2403763488	10182505537	43133785636	182717648081	774004377960

Go back to Part XVII.